Propeller.



PATENTED AUG. 28, 1906.

R. A. WORKMAN.

PROPELLER.

APPLICATION FILED AUGJ. 1904.

3 SHEETS-SHEET 2.

PATENTED AUG. 28, 1906.

R. A. WORKMAN.

PROPELLER.

APPLICATION FILED AUG.1. 1904.

3 SHEETS-SHEET 3.

fiazm anwm an) 5 972m ffirmm UNITED STATES.

ROBERT A. WORKMAN', OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR,

.BY DIRECT AND MESNE ASSIGNMENTS,

PHILADELPHIA, PENN SYLVANIA.

'TO LUTHER D. LOVEKIN, OF

.PRQPELLER.

Specification of Letters Patent.

Patented Aug. 28, 1906.

Application filed August 1, 1904- Serial No. 219,099-

with the propellers in common usethat is,

by my invention I desire to provide a propeller which in a given time and with a given consumption of fuel shall be capable of driv mg the vessel on which it is used through a greater distance than has previously been possible or from another standpoint, shall be capable of driving. a vessel through a given distance in a given tinie with the consumption of less fuel, and consequently at a'less cost, than is at present possible with propellers of the ordinary type.

It is further the object of my invention to provide a propeller capable of securing the above-named object, with cooperating structures particularly designed to act with it, to

secure such a fiow of water toward and from it as-Will retard the motion of the vessel through, the water to a minimum extent.

These objects I attain as hereinafter set forth, reference being had to the accompanying drawings, in which- Fi ure 1 is a side elevation of a part of a vesse equipped with propellers constructedaccording to my invention and showing one of said propellers with its cooperating parts. Fig. 2 1s a rear end elevation of the vessel shown in Fig. 1, showing one of the propellers in position and illustrating the end construction of the shaft-tube for the second propeller, which for the sake of clearness is not shown. Fig. 3 is an enlarged sectional elevation of the shaft-tube and stationary dome used in connection with my improved propeller and illustrating the detaiLconstruction of said parts. Fi 4 is an elevation of my improved prope er looking forward. Fig. 5 is a side elevation of the propeller shown in Fig. 4. Figs. 6, 7, and 8 are sectional elevations illustrating various'forms of the disk on which are carried the blades of the re eller. Fi 9 is a transverse sectional el vation il ustrating a method which may be employed for propellers of large sizes for securing the blades to their supporting-disk; and Fig. 10 is a side elevation showing a modification of my invention in which the disk and shell to the rear'of the same are made integral, said shell beingunder these conditions free to revolve instead of bein rigidly supported from the framework 0? the ship, as m the other form of the invention.

It has long been a well-known fact that half of an ordinary propeller-blade nearest the hub is relatively inei'licient under operating conditions, since the elements of its surface lie at such an angle to the plane of revolution of the propeller that said portion acts to a great extent upon the water so as to merely churn the same without doin useful work in driving the vessel ahead. 1%1 other words, these lnner portions of propellerblades of the ordinary construction are necessarily so placed as to require work to be done in turning the propeller, of which work but a relatively small part is effective to propel the ship.

In order to provide a propeller which shall have the same eflective surface without re quiring an increased diameter for a given power, I increase the number of blades employed, securing a construction such as is shown in the drawin s herewith.

In the drawings, represents the body of a vessel having aair of propellers, one of which is shown at I3, while their detail construction is illustrated in Figs. 4 and 5. Each pro eller includes asupporting-disk, which pro erably consists of a cylindrical shell having strengthening-ribs band a central hub b properly ored to receive the propeller-shaft C, upon which the disk is keyed and held 1n.

place by means of a nut c in the usual manner. Integral with the disk B or bolted thereto, as illustrated in Fi 9, are any required number of propellerlades b -'in the present instance sixand it will be noted that the length of said blades isin the case illustrated slightly less than the radius of the disk in which they are carried. The active portions of these blades are helical surfaces and, as above noted, may be best described as each consisting of the outer half of a ropeller-blade of the ordinary type. The 01- .4 vessel of which they are merely an extent e blades and when said blades are made inde endently to it is provided with recesses, as s own in Fi 9, into which fit flanges formed as part 0 the blades, said flan es entering the recesses so as to be flush with the surface of the disk, and being held therein by bolts, as indicated.

In order that'the disk B may not retard the motion of the ship in the water I provide a construction supported from the side of said vessel, as illustrated in Fi 3. This will be seen to consist substantia ly of a cylindrical shell A, having its outer end closed by a casting a, provided with a stern-bearing for the after-end of the propeller-shaft. his casting is supported from the main frame of the vessel in any desired manner and has its outer face dished, as shown, in order to minimine the braking efiect occur-ring by reason t or the water filling the s ace between it and the adjacent face of the isk ofthe ropelier.

As shown in Fig. 3, the body of the s aft-tube consists of plates 0. entering a suitable recessed ortion of the casting a, so as to be flush with the peri' holy of the same, and supported at interval; by means of a series of ulkheads formed by concentrically-curved an les a and a braced and connected to get erbyplates a. 'Certain of these outer angles are preferabl merely extensions of the ribs or side mem ers of the vessels frame Work and project from the body of said vessel through t at portion which is intersected by the said shaft-tube. Within the inner set ofangles a is a second tube at, directly surroundin shaft 0, and, as shown in Figs. 1 and 2, thee aft-tube A is continued forwardly until its plates intersect .theplating of the sien, as indicated by dotted lines. 7

. order that the water to the rear ofth'evessel shall not exert a suction upon therear face of the disk or create undue disturbance of the water, I provide a dome-shaped shell. D of circular section and made with its sides of parabolic curvature. This curvature is determined by a consideration of the normal velocity of the vesseland the time taken for a 1 particle of water tofall under the actionof gravit from the circumference to the center of the propeller-disk. shown in Figs. 3. and 3, this dome is sup or'ted, from the sideof the vessel bf means'o the, ship-frames and a brace 11, so t at its circular lease is adjacent tothe rear face of the-disk of the impeller. Said'base'inthe resent instance is ormed'by the casting d, w 'ch, like the castings of the shaft-tube,- is madecdisheiso asto reduce the water frictionbetween it and the pro eller-f disk to a minimum, there being a man ole in the casting closed by a cover (1, through which access m'aybe had to the nuts, &c.,'

at the end-of the propeller-shaft. The point seats? of the dome-shell also consists of a casting (i and both of said castings are slightly recessed, so as to permit the plates (1 forming the body of the dome, to fit flush with their surfaces. These plates are carried by the outwardly-curved angles d of the shi s framework, which angles extend from t e vessels body into the shell D through the s ace or o ening G. (Shown in full lines in ig. 2 and hy dotted. lines in Fig. 1.) It will be noted that the disk upon which the propeller-blades are carried is not necessarily of the construction shown in Figs. 5 and 7, since, if desired, itstwo faces may be dished, as shown at B in Fi 8, or it inay be made as a pulley or fly-whee having a single web, as illustrated at B in Fig. 6.

Under operating conditions it will be seen that'water is free to how to the propellerblades over the shaft-tube A and after it has left said blades is permitted to flow to the rear of the vessel over the double curved or parabolic surface of the dome D in a manner propeller is secured. Such action also re sults in increased economy of fuel and ermitsthe attainment of higher speeds tan would otherwise be possible.

if, desired, I may, as shown in F 10, make the disk as part of the shell the Whole resultin structure D being free to revolv'e and having the blades in the same relative ositions as before.

I c aim as my inventioni Y 1. The combination with the hull of a vessel of a substantially cylindrical extension therefrom, a shaft in said extension, and apropeller on said shaft, the end of the extension adjacent to said propeller being proyided with a concave head, substantially as described.

2. The combination with the hull of a vessel of a substantially c lindrical shaft-tube, a shaft therein, a propel or on said shaft and a stationary shell to. the rear of the pro eller,

the shelland the-tube being provide vwithconcave ,heads adjacent to said propeller,

substantially as described.

3. The combination with the hull of a vessel of a substantially cylindrical extension from the same, a casting in the end of said extension, a shaft in'the extension having a bearing in said casting and a disk onthe shaft of substanisks and be-. rmed conc'avethereto, substantially as having blades,- said casting ein' "tiaily the same diameter as; said 5 mg 0 described.

a. The combination-with the hull of ago end, a stationary and substantially conical shell to the rear of said extension also having .a casting in one end, a disk on said shaft of substantially the same diameter as the two castings and blades projecting from said disk, said two castings being concave relatively to said disk, substantially as described.

5. The combination with the hull of a vessel, of an extension to the same, a substantially conical shell supported from the vessel and forming a continuation of said extension, a shaft, a disk supported thereon between the shell and he extension from the hull, and blades on said disk, there being a head for the conical shell adjacent to the disk, and said shell having one opening in said head adjacent to the end of the shaft and. a second opening into the interior of the vessels hull, substantially as described.

6. The combination with the hull of a vessel of a tubular extension from the same, a substantially conical shell having its base adjacent to'the rear of said extension a propeller and a shaft in the extension supportmg said propeller between the end of said extension and the shell, there being a normally closed openin throu h the base of theshell adjacent to t e sha t, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribin witnesses.

1301313111 A. WORKMAN. Witnesses: WILLIAM E. BRADLEY,

' Jos. H. KLEIN. 

